EP0829454B1 - Nichtstöchiometrisches Ytterbiumphosphatpulver mit niedrigem Infrarot-Reflexionsvermögen - Google Patents

Nichtstöchiometrisches Ytterbiumphosphatpulver mit niedrigem Infrarot-Reflexionsvermögen Download PDF

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EP0829454B1
EP0829454B1 EP19970402052 EP97402052A EP0829454B1 EP 0829454 B1 EP0829454 B1 EP 0829454B1 EP 19970402052 EP19970402052 EP 19970402052 EP 97402052 A EP97402052 A EP 97402052A EP 0829454 B1 EP0829454 B1 EP 0829454B1
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ytterbium
phosphate
range
powder
aqueous
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EP0829454A1 (de
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Yasushi Takai
Yuji Kimura
Shigeru Sakai
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Shin Etsu Chemical Co Ltd
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Shin Etsu Chemical Co Ltd
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    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
    • C09D11/00—Inks
    • C09D11/50—Sympathetic, colour changing or similar inks
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B25/00—Phosphorus; Compounds thereof
    • C01B25/16—Oxyacids of phosphorus; Salts thereof
    • C01B25/26—Phosphates
    • C01B25/37—Phosphates of heavy metals
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B25/00—Phosphorus; Compounds thereof
    • C01B25/16—Oxyacids of phosphorus; Salts thereof
    • C01B25/26—Phosphates
    • C01B25/45—Phosphates containing plural metal, or metal and ammonium

Definitions

  • the present invention relates to a powder of ytterbium phosphate of low infrared reflectivity having a non-stoichiometric phosphorus to ytterbium molar ratio or, more particularly, to a powder of ytterbium phosphate having an overstoichiometric phosphorus content relative to ytterbium which exhibits a remarkably low infrared reflection so as to be useful as an infrared-absorbing agent in an invisible ink for printing of an information data pattern, such as bar code patterns, optically detectable only by using an infrared detecting means but invisible to naked eyes or so-called stealth code patterns.
  • an information data pattern such as bar code patterns
  • a bar code pattern is usually formed by printing a seemingly randomized stripe pattern on the surface of a substrate with a colored or, in most cases, black printing ink containing a black pigment such as carbon black.
  • the bar code patterns formed by printing with such a black ink though convenient in respect of good recognizability by naked eyes, on the other hand, have some problems due to the visibility of the pattern.
  • One of the problems is that, because the bar code pattern occupies a substantial area on the substrate surface, decorativeness of the goods bearing the bar code pattern is greatly limited or decreased thereby not to allow a fully decorative design of, for example, packages as desired.
  • the second of the problems is that, because the bar code pattern is readily and directly recognizable by any person handling the materials, secrecy of the information expressed by the bar code pattern cannot be secured sometimes.
  • inorganic infrared-absorbing materials or inorganic materials having low infrared reflectivity but high reflectivity in the visible wavelength region are also under investigations.
  • inorganic infrared-absorbing materials or inorganic materials having low infrared reflectivity but high reflectivity in the visible wavelength region are also under investigations.
  • Japanese Patent Kokai 7-53946 proposes use of a powder of ytterbium phosphate as an infrared-absorbing agent useful as an ingredient in invisible printing inks.
  • the ytterbium phosphate disclosed there is an orthophosphate of ytterbium, which is one of the rare earth elements having an atomic number of 70, expressed by the formula YbPO 4 .
  • the ytterbium phosphate powder was prepared by a process in which a blend of ytterbium oxide Yb 2 O 3 and phosphorus pentoxide P 2 O 5 was melted by heating at 1300 °C for 2 hours in a platinum crucible and a solid obtained by annealing the melt, which was identified to be ytterbium orthophosphate by the X-ray diffractometric study, was pulverized into a powder.
  • the rate of annealing is so adjusted that the crystallites forming the particles of the powder may have a diameter in the range from 5 to 200 nm in order to have high infrared absorptivity or low infrared reflectivity and the particles have an average particle diameter of 0.01 to 0.1 ⁇ m with a maximum particle diameter not exceeding 1 ⁇ m in order not to exceed the thickness of films formed by printing with a printing ink containing the powder.
  • ytterbium compounds in general such as oxide and hydroxide, exhibit low infrared reflectivity, the infrared reflectivity of these compounds is not low enough as compared with the phosphate and Tajima teaches that the infrared reflectivity of the ytterbium phosphate powder can be controlled by adequately selecting the annealing rate of the melt.
  • the present invention accordingly has an object to provide a novel ytterbium phosphate-based powder material which can be prepared at low costs and is useful as an infrared-absorbing agent in an invisible but infrared-detectable printing ink suitable for printing of an information data pattern such as stealth bar code patterns.
  • the present invention provides a powder of non-stoichiometric ytterbium phosphate having a phosphorus to ytterbium molar ratio in the range from 1.08 to 2.00, of which the particles have an average particle diameter in the range from 0.1 ⁇ m to 5 ⁇ m and the crystallites forming the particles have a diameter in the range from 20 nm to 40 nm.
  • the non-stoichiometric ytterbium phosphate powder of the invention need not have a high purity of ytterbium relative to the rare earth elements but can be a mixture or combination of rare earth phosphates, of which at least 65% by moles is ytterbium phosphate, without substantial adverse influences on the infrared-absorbing or infrared-reflecting characteristics of the non-stoichiometric ytterbium phosphate powder.
  • the rare earth elements to be combined with ytterbium can be any of the rare earth elements including yttrium and the elements having an atomic number of 57 to 71.
  • the above defined non-stoichiometric ytterbium phosphate powder or mixed rare earth phosphate powder can be prepared by a precipitation method in which an aqueous solution of a water-soluble ytterbium salt or mixed rare earth salts and an aqueous solution of phosphoric acid are blended together at 50 to 100 °C in a specified phosphorus to rare earths molar proportion of 1.2 to 6.0 to precipitate a phosphate powder of ytterbium or mixed rare earths which is recovered from the precipitation medium and calcined at a temperature of 300 to 1100 °C for 2 to 15 hours in an oxidizing atmosphere followed by disintegration or pulverization of the calcined mass to such an extent that the powder may have the above mentioned specific average particle diameter.
  • the figure is an X-ray diffractometric diagram of the non-stoichiometric ytterbium phosphate powder prepared in Example 2 showing peaks assignable to both of ytterbium orthophosphate YbPO 4 and ytterbium trimetaphosphate Yb(PO 3 ) 3 .
  • the non-stoichiometric ytterbium phosphate powder of the present invention is characterized by the specific non-stoichiometric phosphorus to ytterbium molar ratio and by the particle characteristics relative to the average particle diameter and the diameter of the crystallites forming the particles.
  • the non-stoichiometric ytterbium phosphate powder of the invention exhibits lower than 40% of the reflectivity on the surface of a powder layer in the wavelength region of 975 to 977 nm assuming a 100% surface reflectivity for the surface of a barium sulfate layer.
  • tervalent ytterbium ions Yb 3+ exhibit strong absorption of infrared light so that compounds, e.g., oxide, hydroxide, phosphate and sulfate, of tervalent ytterbium ions in general absorb infrared light although the strength of infrared absorption depends on the types of the compounds.
  • compounds e.g., oxide, hydroxide, phosphate and sulfate
  • the infrared absorptions of ytterbium hydroxide and oxide are 26% and 47%, respectively.
  • Phosphates of tervalent ytterbium are the most promising as an infrared absorbing agent in infrared-detectable invisible inks in respect of the outstandingly low infrared reflection on the powder surface.
  • the rare earth element forming the non-stoichiometric phosphate of the invention need not be high purity ytterbium but can be a combination of ytterbium with one or more of other rare earth elements provided that at least 65% by moles of the combined rare earth elements be ytterbium.
  • the most characteristic feature of the inventive ytterbium phosphate powder is that the phosphate is non-stoichiometric with a molar ratio of phosphorus to ytterbium or combined rare earth elements in the range from 1.08 to 2.00 or, preferably, from 1.08 to 1.20.
  • a molar ratio of phosphorus to ytterbium or combined rare earth elements in the range from 1.08 to 2.00 or, preferably, from 1.08 to 1.20.
  • the efficiency of infrared absorption of a powder is high with low surface reflection when each of the particles consists of a single crystallite and the surface of the particles is smooth without defects such as fissures and cracks detectable on a scanning electron microscopic photograph. Further, the efficiency of infrared absorption is increased by increasing the diameter of the crystallites.
  • the disclosure of Japanese Patent Kokai 7-53946 teaches that the diameter of the crystallites of ytterbium orthophosphate should be in the range from 5 to 200 nm or, preferably, from 10 to 100 nm and the particles obtained by pulverization of the solidified melt should have an average particle diameter in the range from 0.01 ⁇ m to 0.1 ⁇ m.
  • the phosphate crystallites forming the particles should have a diameter in the range from 20 nm to 40 nm and the particles should have an average particle diameter in the range from 0.1 ⁇ m to 5 ⁇ m or, preferable, from 0.1 ⁇ m to 0.2 ⁇ m.
  • the efficiency of infrared absorption of the powder would be greatly decreased even if the requirement for the non-stoichiometric phosphorus to ytterbium molar ratio is satisfied.
  • the printed ink layer formed by gravure printing has a thickness of 2 ⁇ m to 5 ⁇ m and the printed ink layer formed by screen printing has a thickness of as large as 20 ⁇ m to 40 ⁇ m so that particles of 5 ⁇ m diameter can be fully embedded in the ink layer.
  • the limitation in the average particle diameter of the phosphate particles should be considered as a factor having influences on the viscosity or consistency of the printing ink containing the particles. Assuming that the formulation of the printing ink relative to the amounts of the vehicle resin and the particulate ingredients be identical, namely, the viscosity of the printing ink is usually increased by decreasing the average particle diameter of the particulate ingredients. Accordingly, the average particle diameter of the ytterbium phosphate powder cannot be too small in order to avoid undue increase in the viscosity of the printing ink formulated therewith.
  • the non-stoichiometric rare earth phosphate powder of the invention is prepared by the precipitation method in which an aqueous solution of a water-soluble salt of ytterbium or a combination of rare earth elements including ytterbium and an aqueous solution of phosphoric acid are blended together to form precipitates of the non-stoichiometric rare earth phosphate in the aqueous medium.
  • the water-soluble salt of ytterbium is selected, though not particularly limitative, from chloride, nitrate and sulfate of ytterbium, of which ytterbium nitrate is preferred because any nitrate residue possibly contained in the phosphate precipitates can be completely removed by thermal decomposition in the calcination treatment of the precipitates.
  • the aqueous solution of the water-soluble ytterbium or mixed rare earth salt is prepared in a concentration in the range from 0.1 to 1.0 mole/liter relative to the element of ytterbium or combined rare earth elements.
  • the aqueous phosphoric acid solution should have a concentration in the range from 0.06 to 2.5 moles/liter.
  • the above prepared two aqueous solutions are then blended together at a temperature in the range from 50 to 100 °C under agitation, preferably, over a period of 180 seconds or shorter so that precipitates of the ytterbium or mixed rare earth phosphate are formed in the aqueous medium. It is optional that the aqueous solution of phosphoric acid is added to the aqueous solution of the rare earth salt or vice versa.
  • the blending proportion of the two aqueous solutions is selected in such a way that the molar ratio of phosphorus in the phosphoric acid to the ytterbium element or the combined rare earth elements in the water-soluble salt is in the range from 1.2 to 6.0.
  • each of the two aqueous solutions before blending is heated and kept at a temperature of 50 °C or higher up to the boiling point so that the precipitation reaction takes place at a temperature in the range from 50 °C to the boiling point of the aqueous precipitation medium.
  • the precipitates of ytterbium phosphate formed in the aqueous precipitation medium are kept as such for 10 to 60 minutes to effect aging of the precipitates at 50 to 100 °C.
  • concentrations and volumes of the two aqueous solutions i.e. the phosphoric acid solution and ytterbium salt solution, are adjusted in such a way that the content of ytterbium element in the precipitation mixture after mixing of the two solution is in the range from 0.05 to 0.2 mole/liter.
  • the precipitates of the non-stoichiometric phosphate of ytterbium or combined rare earth elements formed in the aqueous precipitation medium are then collected by filtration or other suitable solid-liquid separating means and dried and calcined at a temperature in the range from 300 to 1100 °C or, preferably, from 300 to 900 °C in an oxidizing atmosphere such as atmospheric air for a length of time in the range from 2 to 15 hours or, preferably, from 2 to 8 hours. It is not always necessary that the precipitates recovered from the aqueous precipitation medium are washed with water to be freed from any electrolytes provided that the ytterbium salt as the starting material is ytterbium nitrate for the reasons mentioned before.
  • the conditions of this calcination treatment are particularly determinative of the crystallite size of the phosphate particles which must be in the range from 20 nm to 40 nm in diameter.
  • the crystallite size would be too large when the temperature is too high or the time is too long in the calcination of the phosphate precipitates while the crystallite size would be too small when the temperature is too low or the time is too short.
  • a quite satisfactory results can be obtained by a calcination treatment at 300 °C for 6 hours.
  • the thus obtained ytterbium phosphate of an overstoichiometric phosphorus content consists mainly of two different crystallographic phases of which one is the orthophosphate of ytterbium YbPO 4 and the other is trimetaphosphate of ytterbium Yb(PO 3 ) 3 by making comparison of the X-ray diffractometric diagram such as the diagram shown in the accompanying drawing with authentic crystallographic X-ray diffraction peak data.
  • the temperature of calcination is low, for example, at 400 °C or below, the predominant crystallographic phase is the orthophosphate of ytterbium.
  • the precipitates after the calcination treatment form a mass of agglomeration so that the mass is disintegrated or pulverized into a powder having a specified average particle diameter in the range from 0.1 to 5 ⁇ m or, preferably, from 0.1 to 0.2 ⁇ m. It is important to avoid overgrinding in the pulverization.
  • Pulverization of the mass obtained by the calcination treatment of the precipitates of ytterbium phosphate is performed preferably by a wet-process method in a liquid pulverization medium by using a suitable pulverizing machine such as a beads mill.
  • the inventive ytterbium phosphate powder is as an infrared-absorbing pigment in an infrared-detectable stealth ink which may be a water-base ink or an organic ink
  • an aqueous slurry of the ytterbium phosphate powder is prepared by adding the unpulverized ytterbium phosphate obtained by calcination in an amount to give a solid content of the mixture not exceeding 30% by weight followed by pulverization in a beads mill.
  • aqueous pulverization medium having a pH not lower than 4, if necessary, by using ammonia water or an aqueous solution of sodium hydroxide.
  • the thus obtained aqueous slurry of the ytterbium phosphate particles is admixed with a silane coupling agent so as to effect a surface treatment of the particles followed by centrifugation to remove a part of the aqueous medium or to adjust the solid content of the slurry so that the remaining aqueous slurry may have a viscosity, though dependent on the average particle diameter of the ytterbium phosphate particles, not to exceed 500 centipoise.
  • the aqueous slurry is admixed with an aqueous solution of a water-soluble resin or an aqueous emulsion of a water-insoluble resin as a binder or vehicle resin followed by a further continued pulverization treatment to give an ink composition for invisible printing.
  • the aqueous slurry obtained in the above described manner is dehydrated to give a dried ytterbium phosphate powder which is then dispersed in an organic solvent in an amount to give a solid content not exceeding 30% by weight and the ytterbium phosphate powder is again pulverized in the organic solvent by using a beads mill.
  • suitable organic solvents include aromatic hydrocarbon solvents such as toluene and xylene and ketone solvents such as methyl ethyl ketone.
  • the pulverization medium is admixed with a surface active agent such as polycarboxylic acid-based ones as a dispersing aid in an amount of 3 to 7% by weight based on the amount of the ytterbium phosphate powder.
  • a surface active agent such as polycarboxylic acid-based ones as a dispersing aid
  • the pulverization mixture is admixed with a silane coupling agent to effect a surface treatment of the particles followed by centrifugation to remove a part of the organic solvent or to adjust the solid content to exceed 50% by weight.
  • the thus obtained organic slurry of the ytterbium phosphate particles is admixed with a solution of a vehicle resin followed by further milling in a beads mill to give the desired organic ink composition.
  • the ytterbium phosphate powder having a non-stoichiometric phosphorus to ytterbium molar ratio is illustrated in more detail by way of Examples and Comparative Examples, which, however, never limit the scope of the present invention in any way.
  • the powder parameters of the ytterbium phosphate powders and mixed rare earth phosphate powders were measured in the following manner.
  • Average particle diameter of the powders was determined by the laser diffraction method.
  • the crystallite diameter was calculated by the Scherrer's method, which is applicable to a crystallite diameter not exceeding 100 nm, utilizing the results obtained in the X-ray diffractometric study.
  • the infrared absorption in % was obtained by measuring the reflectivity in % of the powder surface using a spectrophotometer at a wavelength of 976 nm and subtracting the reflectivity in % from 100% taking the reflectivity of a barium sulfate powder as 100%.
  • a 1 liter portion of an aqueous solution of ytterbium nitrate in a concentration of 1 mole/liter as prepared by dissolving ytterbium oxide in 55% excess of nitric acid was poured into 9 liters of a 0.222 mole/liter aqueous solution of phosphoric acid at 76 °C taking 141 seconds.
  • the content of ytterbium element in the precipitation mixture after blending of the two solutions was 0.1 mole/liter.
  • concentrations and volumes of the two aqueous solutions corresponded to a phosphorus to ytterbium molar ratio of 2.0.
  • the precipitates formed in the aqueous medium were collected by filtration and, without washing with water, dried and calcined in air at 300 °C for 4 hours followed by wet-process pulverization in water to give a powder having an average particle diameter of 0.12 ⁇ m.
  • Table 1 summarizes the results of the evaluation tests undertaken for the powder separated from the aqueous pulverization medium and then dried including the phosphorus to ytterbium molar ratio, average particle diameter in ⁇ m, diameter of the crystallites in nm and infrared absorption in %.
  • the experimental procedure was about the same as in Example 1, in which 1 liter of an aqueous solution of ytterbium nitrate in a concentration of 0.5 mole/liter as prepared by dissolving ytterbium oxide in 45% excess of nitric acid was poured into 9 liters of a 0.067 mole/liter aqueous solution of phosphoric acid at 80 °C taking 7 seconds.
  • the content of ytterbium element in the precipitation mixture after blending of the two solutions was 0.05 mole/liter.
  • concentrations and volumes of the two aqueous solutions corresponded to a phosphorus to ytterbium molar ratio of 1.2 instead of 2.0 in Example 1.
  • the precipitates formed in the aqueous medium were collected by filtration and, without washing with water, dried and calcined in air at 300 °C for 2 hours. Pulverization of the calcined precipitates was conducted in toluene instead of water.
  • Table 1 summarizes the results of the evaluation tests of the thus obtained ytterbium phosphate powder undertaken in the same manner as in Example 1.
  • Figure of the accompanying drawing is an X-ray diffractometric diagram of the ytterbium phosphate powder obtained here with the abscissa given in degrees for 2 ⁇ (Cu K ⁇ ).
  • the experimental procedure was about the same as in Example 1, in which 2 liters of an aqueous solution of ytterbium nitrate in a concentration of 0.5 mole/liter as prepared by dissolving ytterbium oxide in 63% excess of nitric acid were poured into 8 liters of a 0.188 mole/liter aqueous solution of phosphoric acid at 76 °C taking 6 seconds.
  • the content of ytterbium element in the precipitation mixture after blending of the two solutions was 0.1 mole/liter.
  • concentrations and volumes of the two aqueous solutions corresponded to a phosphorus to ytterbium molar ratio of 1.5 instead of 2.0.
  • the precipitates formed in the aqueous medium were collected by filtration and, without washing with water, dried and calcined in air at 300 °C for 8 hours. Pulverization of the calcined precipitates was conducted in isopropyl alcohol instead of water.
  • Table 1 summarizes the results of the evaluation tests of the thus obtained ytterbium phosphate powder undertaken in the same manner as in Example 1.
  • the experimental procedure was about the same as in Example 1, in which 1 liter of an aqueous solution of ytterbium nitrate in a concentration of 0.2 mole/liter as prepared by dissolving ytterbium oxide in 63% excess of nitric acid was poured into 1 liter of a 0.3 mole/liter aqueous solution of phosphoric acid at 78 °C taking 9 seconds.
  • the content of ytterbium element in the precipitation mixture after blending of the two solutions was 0.1 mole/liter.
  • concentrations and volumes of the two aqueous solutions corresponded to a phosphorus to ytterbium molar ratio of 1.5 instead of 2.0.
  • the precipitates formed in the aqueous medium were collected by filtration and, without washing with water, dried and calcined in air at 900 °C for 3 hours. Pulverization of the calcined precipitates was conducted in n-butyl alcohol instead of water.
  • Table 1 summarizes the results of the evaluation tests of the thus obtained ytterbium phosphate powder undertaken in the same manner as in Example 1.
  • the experimental procedure was about the same as in Example 1, in which 4 liters of an aqueous solution of ytterbium nitrate in a concentration of 0.5 mole/liter as prepared by dissolving ytterbium oxide in 45% excess of nitric acid were poured into 6 liters of a 0.667 mole/liter aqueous solution of phosphoric acid at 77 °C taking 5 seconds.
  • the content of ytterbium element in the precipitation mixture after blending of the two solutions was 0.2 mole/liter.
  • concentrations and volumes of the two aqueous solutions corresponded to a phosphorus to ytterbium molar ratio of 2.0.
  • the precipitates formed in the aqueous medium were collected by filtration and, without washing with water, dried and calcined in air at 900 °C for 3 hours. Pulverization of the calcined precipitates was conducted in water.
  • Table 1 summarizes the results of the evaluation tests of the thus obtained ytterbium phosphate powder undertaken in the same manner as in Example 1.
  • the experimental procedure was about the same as in Example 1, in which 4 liters of an aqueous solution of ytterbium nitrate in a concentration of 0.5 mole/liter as prepared by dissolving ytterbium oxide in 50% excess of nitric acid were poured into 6 liters of a 0.667 mole/liter aqueous solution of phosphoric acid at 76 °C taking 10 seconds.
  • the content of ytterbium element in the precipitation mixture after blending of the two solutions was 0.2 mole/liter.
  • concentrations and volumes of the two aqueous solutions corresponded to a phosphorus to ytterbium molar ratio of 2.0.
  • the precipitates formed in the aqueous medium were collected by filtration and, without washing with water, dried and calcined in air at 300 °C for 6 hours. Pulverization of the calcined precipitates was conducted in water.
  • Table 1 summarizes the results of the evaluation tests of the thus obtained ytterbium phosphate powder undertaken in the same manner as in Example 1.
  • the experimental procedure was about the same as in Example 1 but the precipitation reaction was conducted by pouring an aqueous phosphoric acid solution into an aqueous ytterbium nitrate solution.
  • 2 liters of a 1 mole/liter aqueous solution of phosphoric acid were poured into 8 liters of an aqueous solution of ytterbium nitrate in a concentration of 0.125 mole/liter as prepared by dissolving ytterbium oxide in 43% excess of nitric acid at 76 °C taking 141 seconds.
  • the content of ytterbium element in the precipitation mixture after blending of the two solutions was 0.1 mole/liter.
  • concentrations and volumes of the two aqueous solutions corresponded to a phosphorus to ytterbium molar ratio of 2.0.
  • the precipitates formed in the aqueous medium were collected by filtration and, without washing with water, dried and calcined in air at 300 °C for 14 hours. Pulverization of the calcined precipitates was conducted in water.
  • Table 1 summarizes the results of the evaluation tests of the thus obtained ytterbium phosphate powder undertaken in the same manner as in Example 1.
  • the experimental procedure was about the same as in Example 7, in which 5 liters of a 0.4 mole/liter aqueous solution of phosphoric acid were poured into 5 liters of an aqueous solution of ytterbium nitrate in a concentration of 0.2 mole/liter as prepared by dissolving ytterbium oxide in 63% excess of nitric acid at 80 °C taking 5 seconds.
  • the content of ytterbium element in the precipitation mixture after blending of the two solutions was 0.1 mole/liter.
  • concentrations and volumes of the two aqueous solutions corresponded to a phosphorus to ytterbium molar ratio of 2.0.
  • the precipitates formed in the aqueous medium were collected by filtration and, without washing with water, dried and calcined in air at 1100 °C for 14 hours. Pulverization of the calcined precipitates was conducted in water.
  • Table 1 summarizes the results of the evaluation tests of the thus obtained ytterbium phosphate powder undertaken in the same manner as in Example 1.
  • the experimental procedure was about the same as in Example 7, in which 2 liters of a 1 mole/liter aqueous solution of phosphoric acid were poured into 8 liters of an aqueous solution of ytterbium nitrate in a concentration of 0.125 mole/liter as prepared by dissolving ytterbium oxide in 42% excess of nitric acid at 76 °C taking 155 seconds.
  • the content of ytterbium element in the precipitation mixture after blending of the two solutions was 0.1 mole/liter.
  • concentrations and volumes of the two aqueous solutions corresponded to a phosphorus to ytterbium molar ratio of 2.0.
  • the precipitates formed in the aqueous medium were collected by filtration and, without washing with water, dried and calcined in air at 900 °C for 15 hours. Pulverization of the calcined precipitates was conducted in water.
  • Table 1 summarizes the results of the evaluation tests of the thus obtained ytterbium phosphate powder undertaken in the same manner as in Example 1.
  • the experimental procedure was about the same as in Example 7, in which 2 liters of a 2.5 mole/liter aqueous solution of phosphoric acid were poured into 8 liters of an aqueous solution of ytterbium nitrate in a concentration of 0.125 mole/liter as prepared by dissolving ytterbium oxide in 45% excess of nitric acid at 76 °C taking 140 seconds.
  • the content of ytterbium element in the precipitation mixture after blending of the two solutions was 0.1 mole/liter.
  • concentrations and volumes of the two aqueous solutions corresponded to a phosphorus to ytterbium molar ratio of 5.0.
  • the precipitates formed in the aqueous medium were collected by filtration and, without washing with water, dried and calcined in air at 900 °C for 2 hours. Pulverization of the calcined precipitates was conducted in water.
  • Table 1 summarizes the results of the evaluation tests of the thus obtained ytterbium phosphate powder undertaken in the same manner as in Example 1.
  • the experimental procedure was about the same as in Example 7, but the ytterbium nitrate solution was replaced with a solution of an ytterbium-yttrium mixed rare earth nitrate of which the molar ratio of ytterbium to yttrium was 99:1.
  • 2 liters of a 1 mole/liter aqueous solution of phosphoric acid were poured into 8 liters of an aqueous solution of the mixed rare earth nitrate in a total rare earth concentration of 0.125 mole/liter as prepared by dissolving ytterbium oxide and yttrium oxide in the above mentioned molar proportion in 33% excess of nitric acid at 75 °C taking 86 seconds.
  • the content of the rare earth elements in the precipitation mixture after blending of the two solutions was 0.1 mole/liter.
  • concentrations and volumes of the two aqueous solutions corresponded to a phosphorus to rare earth elements molar ratio of 2.0.
  • the precipitates formed in the aqueous medium were collected by filtration and, without washing with water, dried and calcined in air at 300 °C for 6 hours. Pulverization of the calcined precipitates was conducted in water.
  • Table 1 summarizes the results of the evaluation tests of the thus obtained mixed rare earth phosphate powder undertaken in the same manner as in Example 1.
  • the experimental procedure was about the same as in Example 11, but the ytterbium to yttrium molar ratio in the mixed rare earth nitrate solution was 79:21 instead of 99:1.
  • 2 liters of a 1 mole/liter aqueous solution of phosphoric acid were poured into 8 liters of an aqueous solution of the mixed rare earth nitrate in a total rare earth concentration of 0.125 mole/liter as prepared by dissolving ytterbium oxide and yttrium oxide in the above mentioned molar proportion in 37% excess of nitric acid at 80 °C taking 153 seconds.
  • the content of the rare earth elements in the precipitation mixture after blending of the two solutions was 0.1 mole/liter.
  • concentrations and volumes of the two aqueous solutions corresponded to a phosphorus to rare earth elements molar ratio of 2.0.
  • the precipitates formed in the aqueous medium were collected by filtration and, without washing with water, dried and calcined in air at 300 °C for 6 hours. Pulverization of the calcined precipitates was conducted in water.
  • Table 1 summarizes the results of the evaluation tests of the thus obtained mixed rare earth phosphate powder undertaken in the same manner as in Example 1.
  • the experimental procedure was about the same as in Example 11, but the ytterbium to yttrium molar ratio in the mixed rare earth nitrate solution was 75:25 instead of 99:1.
  • 2 liters of a 1 mole/liter aqueous solution of phosphoric acid were poured into 8 liters of an aqueous solution of the mixed rare earth nitrate in a total rare earth concentration of 0.125 mole/liter as prepared by dissolving ytterbium oxide and yttrium oxide in the above mentioned molar proportion in 37% excess of nitric acid at 76 °C taking 150 seconds.
  • the content of the rare earth elements in the precipitation mixture after blending of the two solutions was 0.1 mole/liter.
  • concentrations and volumes of the two aqueous solutions corresponded to a phosphorus to rare earth elements molar ratio of 2.0.
  • the precipitates formed in the aqueous medium were collected by filtration and, without washing with water, dried and calcined in air at 300 °C for 6 hours. Pulverization of the calcined precipitates was conducted in water.
  • Table 1 summarizes the results of the evaluation tests of the thus obtained mixed rare earth phosphate powder undertaken in the same manner as in Example 1.
  • the experimental procedure was about the same as in Example 11, but the ytterbium to yttrium molar ratio in the mixed rare earth nitrate solution was 65:35 instead of 99:1.
  • 2 liters of a 1 mole/liter aqueous solution of phosphoric acid were poured into 8 liters of an aqueous solution of the mixed rare earth nitrate in a total rare earth concentration of 0.125 mole/liter as prepared by dissolving ytterbium oxide and yttrium oxide in the above mentioned molar proportion in 39% excess of nitric acid at 76 °C taking 175 seconds.
  • the content of the rare earth elements in the precipitation mixture after blending of the two solutions was 0.1 mole/liter.
  • concentrations and volumes of the two aqueous solutions corresponded to a phosphorus to rare earths molar ratio of 2.0.
  • the precipitates formed in the aqueous medium were collected by filtration and, without washing with water, dried and calcined in air at 300 °C for 6 hours. Pulverization of the calcined precipitates was conducted in water.
  • Table 1 summarizes the results of the evaluation tests of the thus obtained mixed rare earth phosphate powder undertaken in the same manner as in Example 1.
  • the experimental procedure was about the same as in Example 11, but the combination of the rare earth elements in the rare earth nitrate solution was a quaternary combination of ytterbium, lanthanum, cerium and terbium in a molar ratio of 80:10:7:3.
  • 2 liters of a 1 mole/liter aqueous solution of phosphoric acid were poured into 8 liters of an aqueous solution of the mixed rare earth nitrate in a total rare earth concentration of 0.125 mole/liter as prepared by dissolving ytterbium oxide, lanthanum oxide, cerium oxide and terbium oxide in the above mentioned molar proportion in 45% excess of nitric acid at 80 °C taking 140 seconds.
  • the total content of the rare earth elements in the precipitation mixture after blending of the two solutions was 0.1 mole/liter.
  • concentrations and volumes of the two aqueous solutions corresponded to a phosphorus to rare earths molar ratio of 2.0.
  • the precipitates formed in the aqueous medium were collected by filtration and, without washing with water, dried and calcined in air at 900 °C for 2 hours. Pulverization of the calcined precipitates was conducted in water.
  • Table 1 summarizes the results of the evaluation tests of the thus obtained mixed rare earth phosphate powder undertaken in the same manner as in Example 1.
  • the experimental procedure was just the same as in Example 15 except that the molar ratio of the four rare earth elements, i.e. ytterbium, lanthanum, cerium and terbium, in the mixed rare earth nitrate solution was 70:15:10:5.
  • Example 2 The experimental procedure was substantially the same as in Example 2 except that the precipitates recovered from the precipitation medium were not calcined at 300 °C but merely vacuum-dried at room temperature for 12 hours and the dried precipitates were disintegrated in a dry process to give a coarser average particle diameter than in Example 2.
  • Table 2 summarizes the results of the evaluation tests of the thus obtained ytterbium phosphate powder undertaken in the same manner as in Example 1.
  • Example 2 The experimental procedure was substantially the same as in Example 2 except that the precipitates recovered from the precipitation medium were not calcined at 300 °C but merely vacuum-dried at 100 °C for 12 hours and the dried precipitates were disintegrated in a dry process to give a coarser average particle diameter than in Example 2.
  • Table 2 summarizes the results of the evaluation tests of the thus obtained ytterbium phosphate powder undertaken in the same manner as in Example 1.
  • the experimental procedure was about the same as in Example 1, in which 2 liters of an aqueous solution of ytterbium nitrate in a concentration of 0.5 mole/liter as prepared by dissolving ytterbium oxide in 17% excess of nitric acid were poured into 8 liters of a 0.188 mole/liter aqueous solution of phosphoric acid at 78 °C taking 5 seconds.
  • the content of ytterbium element in the precipitation mixture after blending of the two solutions was 0.1 mole/liter.
  • concentrations and volumes of the two aqueous solutions corresponded to a phosphorus to ytterbium molar ratio of 1.5 instead of 2.0.
  • the precipitates formed in the aqueous medium were collected by filtration and, after washing with water, dried and calcined in air at 300 °C for 7 hours. Pulverization of the calcined precipitates was conducted in a dry process instead of the wet process in water.
  • Table 2 summarizes the results of the evaluation tests of the thus obtained ytterbium phosphate powder undertaken in the same manner as in Example 1.
  • the experimental procedure was about the same as in Comparative Example 3 except that calcination of the dried precipitates was conducted for 2 hours at 800 °C instead of 7 hours at 300 °C.
  • Table 2 summarizes the results of the evaluation tests of the thus obtained ytterbium phosphate powder undertaken in the same manner as in Example 1.
  • the experimental procedure was about the same as in Comparative Example 3, in which 2 liters of an aqueous solution of ytterbium nitrate in a concentration of 0.25 mole/liter as prepared by dissolving ytterbium oxide in 17% excess of nitric acid was poured into 8 liters of a 0.075 mole/liter aqueous solution of phosphoric acid at 78 °C taking 12 seconds.
  • the content of ytterbium element in the precipitation mixture after blending of the two solutions was 0.05 mole/liter.
  • concentrations and volumes of the two aqueous solutions corresponded to a phosphorus to ytterbium molar ratio of 1.2 instead of 1.5.
  • the precipitates formed in the aqueous medium were collected by filtration and, after washing with water, dried and calcined in air at 300°C for 7 hours. Pulverization of the calcined precipitates was conducted in a dry process instead of the wet process in water.
  • Table 2 summarizes the results of the evaluation tests of the thus obtained ytterbium phosphate powder undertaken in the same manner as in Example 1.
  • the experimental procedure was about the same as in Comparative Example 5 except that the precipitation reaction was conducted at 76 °C instead of 78 °C and the ytterbium nitrate solution was added to the phosphoric acid solution taking 14 seconds instead of 12 seconds.
  • the precipitates were calcined, without washing with water, in air for 5 hours at 1400 °C instead of 7 hours at 300°C.
  • Table 2 summarizes the results of the evaluation tests of the thus obtained ytterbium phosphate powder undertaken in the same manner as in Example 1.
  • the experimental procedure was about the same as in Example 1, in which 2 liters of an aqueous solution of ytterbium nitrate in a concentration of 0.5 mole/liter as prepared by dissolving ytterbium oxide in 63% excess of nitric acid were poured into 8 liters of a 0.25mole/liter aqueous solution of phosphoric acid at 80 °C taking 5 seconds.
  • the content of ytterbium element in the precipitation mixture after blending of the two solutions was 0.1 mole/liter.
  • concentrations and volumes of the two aqueous solutions corresponded to a phosphorus to ytterbium molar ratio of 2.0.
  • the precipitates formed in the aqueous medium were collected by filtration and, without washing with water, dried and calcined in air at 1250 °C for 5 hours. Pulverization of the calcined precipitates was conducted in n-butyl alcohol instead of water.
  • Table 2 summarizes the results of the evaluation tests of the thus obtained ytterbium phosphate powder undertaken in the same manner as in Example 1.
  • Precipitates of ytterbium phosphate were prepared by the simultaneous introduction of 1 liter of a 1.2 moles/liter aqueous solution of ytterbium nitrate prepared by dissolving ytterbium oxide in 17% excess of nitric acid and 0.5 liter of a 1 mole/liter ammonia water into 0.5 liter of a 2.4 moles/liter aqueous solution of ammonium phosphate at 80 °C taking 60 minutes.
  • the content of ytterbium element in the precipitation mixture after blending of the solutions was 0.6 mole/liter.
  • concentrations and volumes of the aqueous solutions corresponded to a phosphorus to ytterbium molar ratio of 1.0.
  • the precipitates formed in the aqueous medium were collected by filtration and, after washing with water, dried and calcined in air at 800 °C for 2 hours. Pulverization of the calcined precipitates was conducted in a dry process.
  • Table 2 summarizes the results of the evaluation tests of the thus obtained ytterbium phosphate powder undertaken in the same manner as in Example 1.
  • the experimental procedure was substantially the same as in Comparative Example 8, in which calcined precipitates of ytterbium phosphate were pulverized in toluene instead of the pulverization in a dry process.
  • Table 2 summarizes the results of the evaluation tests of the thus obtained ytterbium phosphate powder undertaken in the same manner as in Example 1.
  • the experimental procedure was substantially the same as in Comparative Example 8, in which precipitates of ytterbium phosphate were prepared by the simultaneous introduction of 1 liter of a 1.2 moles/liter aqueous solution of ytterbium nitrate prepared by dissolving ytterbium oxide in 45% excess of nitric acid and 0.5 liter of a 7 moles/liter ammonia water into 0.5 liter of a 6 mole/liter aqueous solution of ammonium phosphate at 76 °C taking 60 minutes.
  • the content of ytterbium element in the precipitation mixture after blending of the solutions was 0.6 moles/liter.
  • concentrations and volumes of the aqueous solutions corresponded to a phosphorus to ytterbium molar ratio of 2.5.
  • the precipitates formed in the aqueous medium were collected by filtration and, after washing with water, dried and calcined in air at 800 °C for 2 hours. Pulverization of the calcined precipitates was conducted in water.
  • Table 2 summarizes the results of the evaluation tests of the thus obtained ytterbium phosphate powder undertaken in the same manner as in Example 1.
  • the experimental procedure was substantially the same as in Comparative Example 8, in which precipitates of ytterbium phosphate were prepared by the simultaneous introduction of 1 liter of a 1.2 moles/liter aqueous solution of ytterbium nitrate prepared by dissolving ytterbium oxide in 17% excess of nitric acid and 0.5 liter of a 7.2 moles/liter ammonia water into 0.5 liter of a 7 moles/liter aqueous solution of ammonium phosphate at 78 °C taking 60 minutes.
  • the content of ytterbium element in the precipitation mixture after blending of the solutions was 0.6 mole/liter.
  • concentrations and volumes of the aqueous solutions corresponded to a phosphorus to ytterbium molar ratio of 3.0.
  • the precipitates formed in the aqueous medium were collected by filtration and, after washing with water, dried and calcined in air at 800 °C for 2 hours. Pulverization of the calcined precipitates was conducted in water.
  • Table 2 summarizes the results of the evaluation tests of the thus obtained ytterbium phosphate powder undertaken in the same manner as in Example 1.
  • the experimental procedure was about the same as in Example 7, but the ytterbium nitrate solution was replaced with a solution of an ytterbium-yttrium mixed rare earth nitrate of which the molar ratio of ytterbium to yttrium was 55:45.
  • 1 liter of a 0.4 mole/liter aqueous solution of phosphoric acid were poured into 1 liter of an aqueous solution of the mixed rare earth nitrate in a total rare earth concentration of 0.2 mole/liter as prepared by dissolving ytterbium oxide and yttrium oxide in the above mentioned molar proportion in 41% excess of nitric acid at 74 °C taking 160 seconds.
  • the total content of the rare earth elements in the precipitation mixture after blending of the two solutions was 0.1 mole/liter.
  • concentrations and volumes of the two aqueous solutions corresponded to a phosphorus to rare earths molar ratio of 2.0.
  • the precipitates formed in the aqueous medium were collected by filtration and, without washing with water, dried and calcined in air at 300 °C for 6 hours. Pulverization of the calcined precipitates was conducted in water.
  • Table 2 summarizes the results of the evaluation tests of the thus obtained mixed rare earth phosphate powder undertaken in the same manner as in Example 1.
  • the experimental procedure was about the same as in Example 7, but the ytterbium nitrate solution was replaced with an aqueous solution of a ytterbium-lanthanum-cerium-terbium mixed rare earth nitrate of which the molar ratio of ytterbium:lanthanum:cerium:terbium was 60:20:14:6.
  • Example No. P rare earth molar ratio Av. particle diameter, ⁇ m Crystallite diameter, nm Infrared absorption, % 1 1.13 0.12 29 69 2 1.09 1.5 32 69 3 1.08 0.8 28 64 4 1.1 3.1 32 79 5 1.6 0.8 30 60 6 1.1 0.9 29 67 7 1.1 0.15 30 62 8 1.14 1.6 33 62 9 1.08 0.13 31 63 10 1.9 0.17 30 60 11 1.18 0.15 22 69 12 1.21 0.11 23 62 13 1.24 0.16 23 62 14 1.28 0.18 24 60 15 1.35 0.17 37 65 16 1.45 0.15 39 64 Comparative Example No.

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Claims (9)

  1. Ein Pulver aus Ytterbiumphosphat mit einer nicht-stöchiometrischen chemischen Zusammensetzung bezüglich des Mol-Verhältnisses von Phosphor zu Ytterbium von 1,08 bis 2,0 und bestehend aus Partikeln mit einem durchschnittlichen Partikeldurchmesser von 0,1 µm bis 5,0 µm, wobei die Partikel aus kistallitem mit einem Durchmesser von 20 nm bis 40 nm gebildet sind.
  2. Phosphatpulver aus einer Kombination von mindestens 2 Seltenerden, wovon mindestens 65 Mol-% Ytterbium ist, mit einer nicht-stöchiometrischen chemischen Zusammensetzung bezüglich des Mol-Verhältnisses von Phosphor zu den Seitenerden in der Kombination von 1,08 bis 2,0 und bestehend aus Partikeln mit einem durchschnittlichen Partikeldurchmesser von 0,1 µm bis 5,0 µm, wobei die Partikel aus Kristalliten mit einem Durchmesser von 20 nm bis 40 nm gebildet sind.
  3. Verfahren zur Herstellung eines Ytterbiumphosphatpulvers enthaltend eine nicht-stöchiometrische Menge an Phosphor bezüglich Ytterbium mit folgenden Stufen:
    a) Vermischen einer wässrigen Losung von Phosphorsäure und einer wässrigen Lösung eines wasserlöslichen Ytterbiumsalzes in einem solchen Anteil, daß das Mol-Verhältnis von Phosphor in der Phosphorsäurelösung zu Ytterbium in der Ytterbiumsalzlösung von 1,2 bis 6,0 beträgt. bei einer Temperatur von 50 bis 100 °C zur Bildung von Ytterbiumphosphatpräzipitaten in einem wässrigen Präzipitationsmedium,
    b) Abtrennen der Ytterbiumphosphatpräzipitate aus dem wässrigen Präzipitationsmedium,
    c) Calcinieren der Ytterbiumphosphatpräzipitate bei einer Temperatur von 300 °C bis 1100 °C für eine Zeitspanne von 2 h bis 15 h und
    d) Pulverisieren der calcinierten Ytterbiumphosphatprazipitate zu einem Pulver in einem solchen Ausmaß daß die Partikel des Pulvers einen durchschnittlichen Partikeldurchmesser von 0,1 µm bis 5,0 µm besitzen.
  4. Verfahren zur Herstellung eines Ytterbiumphosphatpulvers nach Anspruch 3, bei dem das wasserlösliche Ytterbium Salz Ytterbiumnitrat ist.
  5. Verfahren zur Herstellung eines Ytterbiumphosphatpulvers nach Anspruch 3, bei dem der Gehalt an dem Ytterbiumelement in dem wässrigen Präzipitationsmedium nach dem Mischen der wässrigen Phosphorsäurelösung und der wässrigen Ytterbiumsalzlösung 0,05 bis 0,2 mol/l des Gesamtvolumens des wässrigen Präzipitationsmediums und der Ytterbiumphosphatpräzipitate beträgt.
  6. Verfahren zur Herstellung eines Ytterbiumphosphatpulvers nach Anspruch 3, bei dem das Vermischen der wässrigen Phosphorsäurelösung und der wässrigen Ytterbiumsalzlösung in Stufe (a) innerhalb von 180 sec durchgeführt/beendet ist.
  7. Verfahren zur Herstellung eines Ytterbiumphosphatpulvers nach Anspruch 3, bei dem die Temperatur der Calcinierung in der Stufe (c) 300 bis 900 °C beträgt.
  8. Verfahren zur Herstellung eines Ytterbiumphosphatpulvers nach Anspruch 3, bei dem die in Stufe (a) gebildeten Ytterbiumphosphatpräzipitate vor der Stufe (b) in dem wässrigen Präzipitationsmedium bei einer Temperatur von 50 bis 100 °C für einen Zeitraum von 10 min bis 60 min gehalten werden.
  9. Druckfarbe, die ein gedrucktes Muster ergeben kann, daß für das nackte Auge unsichtbar, für ein Infrarotdetektionsmittel jedoch detektierbar ist und aufweist:
    (A) ein flüssiges Medium
    (B) einen in dem flüssigen Medium gelösten oder dispergierten Harzträger und
    (C) ein Ytterbiumphosphatpulver mit einer nicht-stöchiometrischen chemischen Zusammensetzung bezüglich des Mol-Verhältnisses von Phosphor zu Ytterbium von 1,08 bis 2,0 und bestehend aus Partikeln mit einem durchschnittlichen Partikeldurchmesser von 0,1 µm bis 5,0 µm, wobei die Partikel aus Kristalliten mit einem Durchmesser von 20 nm bis 40 nm geformt sind, dispergiert in dem flüssigen Medium.
EP19970402052 1996-09-13 1997-09-03 Nichtstöchiometrisches Ytterbiumphosphatpulver mit niedrigem Infrarot-Reflexionsvermögen Expired - Lifetime EP0829454B1 (de)

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US9150428B2 (en) 2011-06-03 2015-10-06 Orbite Aluminae Inc. Methods for separating iron ions from aluminum ions
US9181603B2 (en) 2012-03-29 2015-11-10 Orbite Technologies Inc. Processes for treating fly ashes
US9260767B2 (en) 2011-03-18 2016-02-16 Orbite Technologies Inc. Processes for recovering rare earth elements from aluminum-bearing materials
US9290828B2 (en) 2012-07-12 2016-03-22 Orbite Technologies Inc. Processes for preparing titanium oxide and various other products
US9353425B2 (en) 2012-09-26 2016-05-31 Orbite Technologies Inc. Processes for preparing alumina and magnesium chloride by HCl leaching of various materials
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US9410227B2 (en) 2011-05-04 2016-08-09 Orbite Technologies Inc. Processes for recovering rare earth elements from various ores
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US6595427B1 (en) 2000-08-31 2003-07-22 Polaroid Corporation Method and apparatus for encoding and decoding information in a non-visible manner
JP3804804B2 (ja) * 2004-04-08 2006-08-02 信越化学工業株式会社 希土類元素りん酸塩組成物及びその製造方法
US7905409B2 (en) * 2005-05-20 2011-03-15 Senshin Capital, Llc Print medium feature encoding and decoding
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US9187221B2 (en) 2011-09-27 2015-11-17 Crown Packaging Technology, Inc. Can ends having machine readable information
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JP6447499B2 (ja) * 2013-08-07 2019-01-09 コニカミノルタ株式会社 研磨材の製造方法及び研磨加工方法
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EP3530352A1 (de) * 2018-02-21 2019-08-28 SASOL Germany GmbH Seltenerdphosphat-aluminiumoxid-verbundwerkstoff zur verwendung in emissionssteuerungskatalysatoren und verfahren zur herstellung davon

Family Cites Families (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2679242A1 (fr) * 1991-07-19 1993-01-22 Rhone Poulenc Chimie Phosphate mixte de lanthane, terbium et cerium, procede de fabrication de ceux-ci a partir de sels insolubles de terres rares.
FR2694299B1 (fr) * 1992-07-29 1994-09-09 Rhone Poulenc Chimie Nouveaux luminophores verts à base de phosphate mixte de lanthane, cérium et terbium, précurseur de ceux-ci et procédés de synthèse.
FR2694281B1 (fr) * 1992-07-29 1994-09-16 Rhone Poulenc Chimie Procédé de préparation de phosphates de terres rares et produits obtenus.
JPH06247711A (ja) * 1993-02-22 1994-09-06 Shin Etsu Chem Co Ltd 希土類元素りん酸塩球状粒子およびその製造方法
JP3527264B2 (ja) * 1993-08-06 2004-05-17 大日本印刷株式会社 赤外線吸収材料
US5569531A (en) * 1993-10-05 1996-10-29 Hitachi Maxell, Ltd. Ink ribbon
EP0646631B1 (de) * 1993-10-05 2004-01-28 Hitachi Maxell Ltd. Lichtemittierende Tintezusammensetzung
JPH0859217A (ja) * 1994-08-24 1996-03-05 Shin Etsu Chem Co Ltd 希土類元素燐酸塩粒子およびその製造方法
JP3527329B2 (ja) * 1994-12-02 2004-05-17 大日本印刷株式会社 赤外線吸収材料及びその製造方法
DE69508212T2 (de) * 1994-12-28 1999-11-04 Hitachi Maxell Tintenzusammensetzung, bedrucktes Material und thermisches Übertragungsaufzeichnungsmaterial

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US8597600B2 (en) 2007-05-21 2013-12-03 Orbite Aluminae Inc. Processes for extracting aluminum from aluminous ores
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US9534274B2 (en) 2012-11-14 2017-01-03 Orbite Technologies Inc. Methods for purifying aluminium ions

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